제출 #1282791

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1282791		icebear	Dynamic Diameter (CEOI19_diameter)	C++20	24 / 100	5092 ms	9116 KiB

diameter

// ~~ icebear ~~
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;

template<class T>
    bool minimize(T &a, const T &b) {
        if (a > b) return a = b, true;
        return false;
    }

template<class T>
    bool maximize(T &a, const T &b) {
        if (a < b) return a = b, true;
        return false;
    }

#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "icebear"
/*END OF TEMPLATE. ICEBEAR AND THE CAT WILL WIN VOI26 */

const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll INF = 1e18 + 27092008;
const int N = 2e5 + 5;
int numNode, numQuery, mod;
vector<int> G[N];
struct Edge {
    int u, v, w;
    int other(int x) {
        return x ^ u ^ v;
    }
} edge[N];
ll f[N], d[N], ans;

void dfs(int u, int par) {
    f[u] = d[u] = 0;
    ll best1 = 0, best2 = 0;
    for(int i : G[u]) {
        int v = edge[i].other(u);
        int w = edge[i].w;
        if (v == par) continue;
        dfs(v, u);
        maximize(f[u], f[v] + w);
        maximize(d[u], d[v]);
        if (best1 < f[v] + w) {
            best2 = best1;
            best1 = f[v] + w;
        } else maximize(best2, f[v] + w);
    }
    maximize(d[u], best1 + best2);
    maximize(d[u], f[u]);
}

void init(void) {
    cin >> numNode >> numQuery >> mod;
    REP(i, numNode - 1) {
        int u, v, w;
        cin >> u >> v >> w;
        edge[i] = {u, v, w};
        G[u].pb(i);
        G[v].pb(i);
    }
}

void process(void) {
    while(numQuery--) {
        int index, weight;
        cin >> index >> weight;
        index = (index + ans) % (numNode - 1);
        weight = (weight + ans) % mod;
        edge[index].w = weight;
        dfs(1, -1);
        cout << (ans = d[1]) << '\n';
    }
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int tc = 1;
//    cin >> tc;
    while(tc--) {
        init();
        process();
    }
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

diameter.cpp: In function 'int main()':
diameter.cpp:95:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   95 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
diameter.cpp:96:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   96 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 0 / 7
• Subtask 4: 0 / 18
• Subtask 5: 0 / 24
• Subtask 6: 0 / 27